Who determines where the distance power should be verified when neutralizing a progressive addition lens?

The correct answer is that the manufacturer determines where the distance power should be verified when neutralizing a progressive addition lens. This is because the manufacturer establishes the specific design and parameters of the lens, which include the location of the distance and near reference points.

Progressive addition lenses (PALs) are designed with zones for different viewing distances that are smoothly integrated, allowing for a gradual change in power from the top of the lens (distance vision) to the bottom (near vision). The manufacturer specifies these areas based on the lens design, including the measurements for where the distance power can be accurately assessed for neutralization purposes.

While the doctor prescribes the lenses and the dispenser may assist in fitting them, it is ultimately the manufacturer who defines the technical specifications essential for lens verification. Understanding these specifications is critical for ensuring that the lenses are functioning as intended in delivering the correct vision at varying distances.